Mold eob cement



STATES oIfARDEs M. PIERE AND BRADFORD s. PIERCE, or NEw BEDFORD, MA'ssAoIiusEfrrs.

Fries.

IIIOLI) FOR CEMENT OR EARTHEN TUBES.`

i Specification of Letters Patent No. 11,440, dated August 1, 1854.

To all whom t may concern: Y ,n

Be it known that we, CHARLES `M. PiERcE and BRADFORD S. PERGE, of New Bedford, in the county of Bristol and State of Massachusetts, have invented a new and useful Improvement in Molds for Cement or Earthen Pipes or Tubes for Drainage, Flues, and other Purposes, of which the following is a full, clear, and exact description, reference being had to the accompanying drawing of the same, which makes part of this specification, and in which- Figure 1 represents a View in perspective of the mold when closed; Fig. 2 represents a longitudinal section through the center of the same; Fig. 3, represents the core in perspective, detached from the mold; Fig. 4

represents a similar view of the case open and detached from the mold, and Fig. `5,

represents four lengths of the pipe made by this mold and laid together on an irregular surface and in acrookedline.

The case (A) of the mold is a sheet of metal bent int-o the form ofthe exterior of the required pipe, which in this instanceA is cylindrical. The meeting edges of the sheet overlap, and haveloops (a) formed on them, through which passes a rod (o) to hold the case firmly closed. The case is so formed that when closed and fastened, it will tend constantly to spring open to acircle of considerably larger `diameter than the pipe to be molded within it, so that the instant the case is unlatched, preparatory to the removal `of the pipe from the mold, it will spring open and free itself from the molded pipe without jarring or shock, thus greatly facilitating the removal of the pipe from the mold. Thismode of detaching the case also leaves the pipe much smoother, and

renders it safe to remove it from the 'mold almost as soon as the plastic material has set, and much sooner than would be safe if the mold were constructed in-the usual man- Ass ner. When the case is closed, it` is placed over the core, (B) the foot (C) of which, is of the `same diameter as the interior of the case, and the stem (B) of the same diameter as the interior or bore of the pipe required; the annular space between the core and the case being equal to the thick ness of the pipe to be molded.

The fillet (c) at the junction of the stem and foot of the core, is a zone of a sphere, and with the upper side of the foot determines the shape of the concave end of the pipe. The upper end of the stem of the core is diminisliedin diameter to form al shoulder (e) for the cap (D) of the mold to rest on. This cap is a cylindricalblock, flat on its upper end, perforated through its axis with an aperture, to allow it to slide freely over the upper end of the stem. The lower end of this cap is in shape the counteiupart of the foot, (c) the concave being the Zone of a hollow sphere, and the precise counterpart of the zone (c) of the foot, and of the shape of one end of the pipe to be made. As the cap of the mold determines the shape of one end of the pipe, and the foot that of the other, and the two are truly spherical and exact counterparts, it follows` that the lengths of pipe made in the mold will fit together, and form equally close joints, whether they be laid on a straight, curved, or zigzag line, which is an object of great importance, especially in draining, where it is difficult to lay pipes in a straight line, without more mechanical skill than the persons usually possess,-who are employed to perform this kind 4of labor.

In using the mold, the core is first set on its foot on a board, table or other 'dat surface, with they stem in an upright position. The case is then placed over the core with its lower end resting on the surface on which the core stands. Its edges are brought together into the position shown in Fig. 1 and the rod (b) is insert-ed through the loops (a) to keep them together. The annular space between the core and the case is now filled with theproper plastic material, (for example a composition of hydraulic cement, coarse sand, sugar in small quantity and water) thoroughly mixed, and of the consistency of sti mortar. This composition should be heaped up around the stem, above the case, and the cap is to be placed over the stem, and pressed down with the force necessary to express the superfluous material, and bring the cap down to the shoulder on the stem, and upon the upper end of the case. The mold is now filled and must stand until the mortar sets which will not be many minutes if freshly calcined hydraulic cement be its basis. When set, the mold is inverted, and the core withdrawn; the mold is next turned back to its former position, and the. cap is removed; finally, the rod is withdrawn, the case springs open, is removed, and the pipe stands complete, and may be set aside for further drying 0r applied to immediate use, as may be preferred. We have made the core of our mold, and

5 the cap, of Wood, and the case, of sheet iron. We do not however confine ourselves to these materials, but reserve the right to employ any subst-ance for the purpose that We may nd suitable. Neither do We confine our- 10 selves to any particular form of mold, either for the inside, outside, or ends of the pipe.

Having thus described the manner of con- 

